Irreversible digital counter and odometer

ABSTRACT

The invention consists of an improved method of constructing and installing digital counting devices, such as odometers, digital time recorders and digital gauges, consisting of a self-destructing and tamperproof &#34;first&#34; or left counting wheel. The numeral of the &#34;first&#34; counting wheel is obliterated by mechanical (or other) means after such numeral has passed the viewing window, thereby making it useless to attempt to &#34;wheel back&#34; the counter to indicate lesser usage, and thereby promoting safety and honesty to and by user, seller and buyer of the machines or devices to which the digital counter is attached. Such improved counters are practically irreversible. The invention accomplishes such goals by abrading, crushing, painting over, expunging, cutting off, slicing through, chiseling off the numeral after it has passed the viewing window, or burning such numerals off by passing them through electrodes which close a circuit when the numeral is moved forward, immediately thereafter interrupting the flow of current, or, in the alternative, being obliterated by magnetic means.

REFERENCE TO PARENT APPLICATION

This application is a division of patent application, Ser. No. 362,751filed May 22, 1973, now U.S. Pat. No. 3,880,351.

SUMMARY OF THE INVENTION

The objects of the invention are to prevent spurious, fraudulent andmisleading changes in digital counting devices, and thereby promotesafety and knowledge of the true status, age and past use of machineryand equipment to which the digital counter is attached, or which it ispart of. Thus, in common digital counting devices known as "odometers",it is the unfortunate practice of turning back the odometer so as tomisrepresent past usage of the vehicle, aircraft, etc., thereby not onlydeceiving a buyer or user, but also endangering life and propertythrough use of improper maintenance schedules, or use of outdated andoverage equipment.

The invention adopts a comprehesive improved method to render digitalcounters practically irreversible at a point where reversibility isbecoming dangerous. This is accomplished by a self-destruct mechanism,which obliterates the numeral on the first (or top-digit) wheel after ithas passed the viewing window. Further security is provided by engravingonto or etching into the wheels of the digital counter permanently theidentifying numbers or letters of the equipment (motor etc.) to whichthe digital counter is annexed, so as to alert every person to anychanges or alterations.

A further object of the invention is to provide an inexpensive yetvirtually invulnerable and tamperproof digital counting device (forbrevity's sake the term "odometer" will be used hereinbelow as anexample for all digital counters). Thus, a standard odometer consistsgenerally of five or six independent wheels, operated by the motion ofthe speedometer shaft (or propeller shaft), which record elapseddistance. The units are from 1/10ths to 10,000s. A small driving catchgenerally rotates the next wheel (to the left) one place or digit foreach complete revolution of the preceding disc. Thus, by way ofillustration, a six-digit odometer would -- under the improved method --turn up to 99,999.9 units -- miles, knots, kilometers etc. -- at whichpoint there would appear in the viewing window an obliterated space onthe first wheel, indicating excessive usage, and making any wheelingback of the odometer useless. Even prior to the end of the first wheel,it would be virtually useless to wheel back the odometer, since the mostanyone could gain would be, in the foregoing example, some 9,000 units,which is a generally acceptable margin on motor vehicles.

A still further object is to relieve law enforcement personnel frompolicing the odometer readings of motor vehicles or other instruments,machinery and equipment.

Other objects and purposes and methods of accomplishing them will appearfrom the specification and drawings, in which:

FIG. 1 is a somewhat enlarged, three-dimensional, oblique view of anodometer with associated housing and certain parts removed for reasonsof drawing simplification and clarity.

FIG. 2 is a view in left-end elevation of the representative odometer ofFIG. 1 shown in mounted relationship with respect to a fragmentarily andsectionally shown motor-vehicle odometer housing, and with onerepresentative embodiment of the present invention associated with theodometer for preventing the reversing of the left odometer wheel, whichindicates the highest numerical power.

FIG. 3 is a somewhat enlarged, fragmentary view partly in elevation andpartly in section taken substantially along the plane and in thedirection indicated by arrows 3--3 of FIG. 2, and shows an obliteratednumeral carried by the left odometer wheel after it has passed theviewing window.

FIG. 4 is a fragmentary side view, partly in elevation, and partly insection, taken substantially along the plane and in the directionindicated by the arrows 4--4 of FIG. 3; it clearly illustrates thenumber-obliterating or number-erasing means of the representative firstalternative of the invention in action.

FIG. 5 is a view of aspect similar to FIG. 2, illustrating a slightlymodified form of the invention, wherein the number-obliterating deviceis an abrasive or grinding means for effectively abrading or grindingaway an odometer numerical, after it has passed the viewing window,rather than a crushing means as shown in the first alternative.

FIG. 6 is a better, somewhat enlarged, staggered plane view takensubstantially along the staggered plane and in the direction indicatedby the arrows 6--6 of FIG. 5, showing the grinding-wheel type ofnumber-obliterating or number erasing means in action.

FIG. 7 is a view generally similar to FIGS. 2 and 5, illustrating afurther representative modification of the number-obliterating means,comprising multiple, circumferentially arranged, sealed, marking-agentcompartments arranged to be effectively opened and applied in an inkingor painting manner to an odometer numeral, only at the instant that ithas passed the viewing window, thereby obliterating same.

FIG. 8 is a fragmentary, somewhat enlarged view taken generally asindicated by arrows 8--8 of FIG. 7, showing the inked-over orpainted-over numeral of the left odometer wheel, after it has passed theviewing window and has been effectively obliterated.

FIG 9 is a fragmentary aspect similar to FIG. 4, showing a furtheralternative, whereby the number-obliterating means removes an exteriornumeral panel from the underlying wheel after it has passed the window.

DESCRIPTION OF THE INVENTION

The invention is an improvement of existing digital counters, with animproved feature of "self-destructing" first (or left) wheel, whichmakes a reversal or "wheeling back" of such counter completely uselessand hence non-feasible.

With reference to FIG. 1, a typical digital counter is illustrated,sometimes known as "odometer", with the housing and certain partsremoved. The odometer is typically driven through a small worm gear,mounted on the speedometer shaft of a vehicle. The motion of thespeedometer shaft, greatly reduced by another gear unit, is transmittedto the odometer. Since a certain number of revolutions of the shaftcorresponds to a certain distance travelled by the wheels of the car,the odometer gives a direct reading of the distance covered, e.g. miles,knots, kilometers, etc. The odometer 10 includes all the odometerwheels, (generally five or six independent wheels bearing equidistantnumerals from 0 to 9 on the outer surface of each wheel). When the rightwheel, which counts customarily 1/10th units, has performed a completerevolution, typically a small driving catch rotates the second wheelfrom the right one place. The process is continued until the left (or"first") wheel 12 which in the illustration indicates 10,000 units isadvanced one place upon completion of a complete turn by the secondwheel from the right.

The first version of the invention is illustrated by FIGS. 1-4. The worm14 is driven by the conventional odometer cable (not illustrated), whichdrives a worm wheel 16 mounted on a shaft 30 which drives directly thesix odometer wheels of the complete odometer 10, each effectively at arate one-tenth of the preceding odometer wheel, as one proceeds from theright end to the left end of the complete odometer and wheel 12.

FIG. 2 shows a left end elevation of odometer 10 shown with afragmentarily and sectionally shown housing 18, generally mounted on adashboard. The wall of the odometer housing 20 which faces the persondriving the vehicle, is penetrated by a transparent viewing window 22.Reference numeral 24 generally designates a presentative first type oftype of obliterating means for obliterating the numeral 28 of the leftodometer wheel 12 which is shown in the specific example in FIG. 2 asconsisting of a crushing wheel 26. Said crushing wheel 26 is inengagement with the exterior of the left odometer wheel 12 at a locationjust past the viewing window 22 and operates by effectively crushing,cracking and flaking away of the brittle numerals 28 of the leftodometer wheel 12. The crushing wheel 26 is located so the periphery ofwheel 26 is in tight contact with the exterior of odometer wheel 12, thecontact being so tight that the teeth 32 of the wheel 26 "cut into" theexterior of odometer wheel 12. The crushing wheel 26 is rotatably drivenalong with the rotation of the left odometer wheel 12 by the inherentfrictional engagement therebetween.

The number-obliterating process according to the first version of theinvention is best illustrated in FIG. 4. The crushing teeth 32 of thecrushing wheel 26, which crush, crack and break away the outer layer 34(or the alternative, raised numerals comprising such outer layer) of theleft odometer wheel 12. FIG. 3 presents a part-elevation view of theimproved process shown in FIG. 4, showing the obliterated numeral 28after it has passed under the crushing wheel 24, which passing wascaused by a complete revolution of the preceding wheel of odometer 10,as described hereinabove.

The first modification illustrated in FIGS. 5 and 6 employs the samereference numerals, followed by the letter a for similar parts andemploys new reference numerals for new parts.

FIG. 5 is a view similar to FIG. 2. The left end elevation of odometer10a inside a fragmentarily and sectionally shown housing 18a; the wallof the odometer housing 20a is penetrated by a transparent viewingwindow 22a. All wheels of odometer 10a are mounted on a common shaft orspindle 30a, upon which is affixed a coupling gear 38, which drives thesecond coupling gear 36, which, in turn, drives a grinding or abradingwheel 26a, that grinds away or abrades the numeral 28a from the leftwheel 12a of odometer 10a. FIG. 6 is a different, staggered plane viewof the process shown in FIG. 5, where the grinding wheel 26a has groundoff and/or abraded numeral 28a carried on the left wheel 12a of theodometer 10a, which left wheel's exterior surface 34a has rotatedopposite the the rotating grinding wheel 26a after passing the viewingwindow 22a. Reference numeral 24a generally designates the modifiedleft-odometer-wheel-number (28a) obliterating or eroding means whichincludes the grinding wheel 26a and two coupling gears 36 and 38.

The second modification shown in FIGS. 7 and 8 employs the samereference numerals, followed by the letter b, for similar parts andemploys new reference numerals for new parts as follows:

FIG. 7 is a view generally similar to FIGS. 2 and 5, illustrating afurther representative modification of the number obliterating means,comprising multiple, circumferentially arranged, sealed (40)compartments or cells containing a marking agent 42, mounted along theouter circumference of a rotating wheel 26b, which contains an outerlayer of the obliterating agent 24b. The latter is positioned forcrushing the plural, externally sealed, individual, circularly arrangedcompartments 40, one by one; said compartments 40 each have a breakableouter exterior covering, and inside a drop of ink or paint, or an inkedsponge or the like 42. Each compartment is crushed or sliced open oncontact with the numeral of the left wheel 12b of odometer 10b, afterthe complete revolution of the next-to-the last odometer wheel hasturned the left wheel 12b one digit past the viewing window 22b mountedon the wall of odometer housing 20b which faces the driver or observer.FIG. 7 is a representative left end elevation of the secondmodification, shown in mounted relationship with a sectionally shownodometer housing 18b. FIG. 8 shows the inked-over and obliteratednumeral 34b of the left odometer wheel 12b, completely inked over asspecifically shown by reference numeral 44.

A third modification is illustrated by FIG. 9; all parts similar topreviously described parts are designated by the same referencenumerals, followed by the letter c. Reference numeral 24c generallydesignates the left-odometer-wheel (12c)-obliterating or erasing means,which in this third modification comprises a chisel 46, closely engagedunder the end of an outer layer 34c which carries the left odometerwheel numbers, so as to strip away each left odometer number after ithas passed the viewing window 22c, which is mounted on the instrumentpanel 20c. Numeral 10c generally illustrates the odometer in this sideview designated as FIG. 9, which is a fragmentary side view, partly inelevation and partly in section.

Not illustrated are similar applications of the invention to otherdigital counters for time, distance, flowthrough etc., all of which arecalled herein "odometer".

What is claimed is:
 1. In combination with a digital counter consistingof two or more movable wheels mounted on a common shaft, rotation ofsaid shaft to effect movement of said wheels with each said wheel beingmovable at a different ratio of movement with respect to the other ofsaid wheels with there being a single said wheel movable at the slowestratio, indicia located on the periphery of said slowest moving wheel, aninlined section of said wheels being observable through a viewing windowformed within a housing, said wheels being rotatably mounted withrespect to said housing, the improvement comprising:an obliterationmeans mounted adjacent said slowest moving wheel, said obliterationmeans to effect obliteration of said indicia upon said slowest movingwheel after said indicia is moved across said viewing window and nolonger observable therethrough, wherein said obliteration meanscomprises; and a chisel mounted upon said housing, said chisel having asharpened forward edge, said forward edge being positioned underneaththe outer layer of material located on said slowest moving wheel,whereby as said slowest moving wheel is moved said forward edge of saidchisel removes said outer layer of material as such passes said viewingwindow.